Method and composition for destroying tree stumps



METHOD AND COMPOSITION FOR DESTROY- ING TREE STUIVIPS No Drawing. Filed May 15, 1958, Ser.No. 735,351

Claims. (CI. 47-58) This invention is concerned with the substantial destruction of tree stumps. It is more directly concerned with a method and composition for facilitating the confiagra'tion'o'f tree stumps.

In general, the removal of substantial numbers of tree stumps in land clearing operations or the like is best carried out employing mechanical, self-propelled equipment such as bulldozers, or, using explosives. 'Suchposi- 'tive techniques which involve uprooting the stumps, however, are not readily adaptable or available, without 'unjustifiable expense or hazards, 'for use by homeowners, farrners, or others who have the occas'ionalproblem of stump removal.

Removal of small numbersof tree stumps, or stumps which cannot be removed by uprooting for various reasons generally efiected by burning the stump to destroy that portion above ground level. Thereafter the area is graded to eliminate evidence of the unsightly stump.

To facilitate the burning it has been the practice to disperse saltpeter (potassium nitrate) through the stump by drilling holes in the exposed "trunk and root structures and disposing portions of the saltpeter in the sewer-a1 holes. "By natural diffusion processes the saltpe'ter would disperse throughout the stump. Kindling of various sorts, such as scrap wood corncobs and the likewould be piled about the stump and ignited. Even though suffi'cient time would elapse 'to permit the substantially complete diffusion of the chemical in the stump b'efore "igniting the stump, unsatisfactory results would be produced. 7

The prevalence of the Dutch elm diseasehas further emphasized the problem of stump removal because arboriculturists currently recommend prompt cutting of dead trees Iand'the destruction of the above-groundjpor- 'tions because they serve as a refuge for the bark beetle that transmits the Dutch "elm disease to healthy trees. Cutting thetrees leaves an unsightly stump; decayed stumps represent aphjysi'c'al hazard "to the public as we'll as to the homeowne''r.

Accordin to this invention there has been 'found a practical and economical composition and method for eil'eeting the substantial removal of unsightly and hazardous stumps by burning. In carrying out this in- 'vention a'water soluble salt a copper ion or a water s'oluble "salt containing a chromium ion is employed as the gloiiv inducing chemical which is dispersed in the stump. Suitable copper salts include "but are not limited to copper chloride, "copper sulfate, copper acetate, copper chlorate, copper dichromate, copper nitrate, and others" Chromium 'ion containing salts innite ttes Patent 0 elude thealkali metal chromates and ldichro mates, e.g.,

sodium eliminate, potassium dich romate'; chromic acid, andothers. I V Although effective results are produced femploymg either the chromium "or -copper salts singly, 'efiiciency of the burning is 'enhancedutilizing admixtures -"of copper and'clrroniium "salts. It has also been "found that the use of water-soluble salts of 'iron, lead, manganese,

Iron iLea'd Manganese Molybdenum bromide acetate chloride alkalim'etal 'ehloride chlorate bromide molybdates" acetate nitrate oxides j citrate sulfates nitrate oxalate sulfate In employing the process of this invention a plurality of holes in a sufficient number and deep enough to receive the selected amount of glow combustion-including composition are drilled in the exposed stem and root structure of the stump. It is preferred that the stem portion be removed as close to the ground level as possible A compositi'on of this invention is introduced, 'preferably in dry form, in the several holes. The dilfusion of the composition through "the stump is permitted to take place. The time required for diffusion depends upon such factorsras moisture content of 'thestump, type of wood, size of stump, amount of glow combustionq'nducing composition employed, :etc To obtain satisfactory results it :is "preferred that the difiusion take place -for "about four months before igniting the stump. Shorter times, however, might :be used. For example, satisfactory results have been reported for a two week diffusion period. :During this period additional amounts 'the burning. The shield which alsoprevents any sparks or embers from Jflying about, can be made from :any Weather and fire resistant sheet material which not substantially deform under the heat conditions experienced during the burning.

The amounts of glow combustion-inducing composition employed will depend upon a number of tactors, primarily the size of the stump and thenature of the wood structure which permits the diflfusionof the composition throughout the stump. In general, an {amount suflicientrtoproduce an equilibrium concentration in-the stump depending arpon its moisture control is'used. Accordingly, f5.2"5 pounds per .stump should be 'used and preferably 10-15 pounds will suffice. Sinall stumps, however, can be removed using lesser amounts. :Because the composition admixture form vmay have a heavy consistency, its use can be facilitated by diluting slightly withwater. Only enough water should be used to permit the easy application without greatly increasing the amount of solution required to incorporate the necessary quantities of composition in the stump structure.

If admixtures 0f the selected water-"soluble salts *are used, the proportions of the respective salts employed Table I vention unexpectedly surpassed the nitrate compositions employed in the prior art.

For best results, preparations for burning the stumps are initiated in the later part of the spring of the year, preferably in May. During this period the stumps are cut to ground level, holes bored, and glow combustion inducing composition introduced into the holes. With Constituent Proportions, percent by Wt.

NaaMoO; I

To illustrate the instant invention, test composition I having the following formulation was employed.

Chemical: Weight percent Cupric chloride 18.75 Sodium dichromate 56.25 Lead acetate 12.50 Manganese chloride 12.50

Prior to use the chemicals were mixed in powdered form and thinned with water to the consistency of heavy transmission oil or thick molasses. I

In controlled tests a plurality of elm stumps were employed. The stumps were cut substantially flush with the ground. Vertical holes l-lVz" in diameter on 5"6" centers were bore 6" deep without penetrating the bottom of the stump. The outside holes were placed 2" from the bark. In addition, holes were bored in the root extensions 3"4" apart as deep as possible without going all the way through.

Ten pounds of the composition per average stump were employed using about 4 pound /2 cup of water-thinned mixture) per hole. Each stump was covered with a 4' x 4' tempered hardboard sheeting shield having a sheet of aluminum foil affixed to the underside. One edge of the shield rested on the ground with the opposed edge being held in an elevated position employing a suitable bracing member.

Monthly inspections were made. Any water which had collected in the holes was removed prior to burning. After about four months the stumps were ignited by covering the stump, including the outside edges and root extensions, with kindling. Prior to igniting, the reflector shields were removed but were replaced after the kindling had been reduced to a bed of coals and the stumps began smouldering. One to three weeks were required to burn the stumps.

Under the same controlled field test conditions, sodium nitrate, ammonium nitrate, and test composition H consisting of 50% CuSO 5H O; 47.5% Na Cr O 2.5%

CrO were employed in a number of stumps.

A panel comprised of forestry experts and members not allied with the forestry profession inspected the results of the field tests and reported their observations. Their conclusions were statistically analyzed and summarized as follows:

Control (no chemical used) 37 It is evident that under the controlled test conditions employed, the eificiency of the compositions of this indiffusion of the composition taking place during the summer, stump burning preferably takes place in late August or early September.

Although elm stumps were employed in the test, it is to be understood that both hardwoo'd and softwood stumps can be substantially destroyed employing the process of this invention. In addition, various modifications in the process set forth in the illustrative embodiment can be made without departingfrom the scope of this invention. For example, the use of the reflector shield is preferred. Satisfactory results, however, can be obtained without the shield. It is therefore apparent that the subject invention is limited only as defined by the specific claims.

We claim:

1. A method for substantially destroying the subterranean portion of a tree stump which co'mprises dispersing at least one compound selected from the group consisting of the water-soluble compounds of copper and chromium within said stump in an amount suflicient to promote the glow combustion thereof, and igniting said stump whereby a substantial subterranean portion of said stump is destroyed.

2. A method in accordance with claim 1 in which an admixture of water-soluble compounds of copper and chromium is dispersed within said stump.

3. A method in accordance with claim 2 in which said admixture comprises copper sulfate and a chromium compound selected from the group consisting of the alkali metal chromates and chromic acid.

4. A method for substantially destroying the subterranean portion of a tree stump which comprises dispersing at least one compound selected from the group consisting of the water-soluble compounds of copper and chromium in combination with at least one compound selected from the group consisting of the water-soluble compounds of iron, lead, manganese, and molybdenum within said stump in an amount suflicient to promote the glow combustion thereof, and igniting said stump whereby a substantial subterranean portion of said stump is destroyed.

5. A method in accordance with claim 4 in which an admixture of water-soluble compounds of copper and chromium in combination with at least one co'mpound selected from the group consisting of the water-soluble compounds of iron, lead, manganese, and molbdenum is dispersed within said stump.

, 6. A method for substantially destroying the subterranean portion of a tree stump which compn'ses boring a plurality of holes in the stem and rot structure of said stump, disposing in said holes a portion of at least one compound selected from the group consisting of the water-soluble compounds of copper and chromium, dispersing an amount of said compound suflicient to promote the glow combustion of said stump therein, and

igniting said stump whereby a substantial subterranean portion of said stump is destroyed.

7. A method in accordance with claim 6 in which an admixture of water-soluble compounds of copper and chromium is dispersed within said stump.

8. A method in accordance with claim 7 in which said admixture comprises copper sulfate and a chromium compound selected from the group consisting of the alkali metal chromates and chromic acid.

9. A method for substantially destroying the subterranean portion of a tree stump which comprises boring a plurality of holes in the stem and root structure of said stump, disposing in said holes a portion of at least one compound selected from the group consisting of the watersoluble compounds of copper and chromium in combination with at least one compound selected from the group consisting of the water-soluble compounds of iron, lead, manganese, and molybdenum, dispersing an amount of said compounds sufficient to promote the glow combustion of said stumps therein, and igniting said stump Whereby a substantial subterranean portion of said stump is destroyed.

'10. A method in accordance with claim 9 in which an admixture of water-soluble compounds of copper and chromium in combination with at least one compound selected from the group consisting of the water-soluble compounds of iron, lead, manganese, and molybdenum is dispersed within said stump.

11. A method in accordance with claim 10 in which an admixture of water-soluble compounds of copper, chromium, lead, and manganese is dispersed within said stump.

12. A composition for promoting the glow combustion of wood which comprises an admixture of the water-soluble compounds of copper, chromium, lead, and manganese.

13. A composition for promoting the glow combustion of wood which comprises an admixture of copper chloride, alkali metal chromates, lead acetate, and manganese chloride.

14. A composition for promoting the glow combustion of wood having the following formulation:

Component: Parts by weight Copper chloride 15-20 Alkali metal chromate -60 Lead acetate 10-15 Manganese chloride 10-15 15. A composition for promoting the glow combustion of wood having the following formulation:

Component: Parts by weight Copper chloride 18.5 Alkali metal chromate 56.5 Lead acetate 12.5

' Manganese chloride 12.5

References Cited in the file of this patent UNITED STATES PATENTS OTHER REFERENCES Publications: Better Homes and Gardens (Magazine), February, 1940, page 90, article, Easy Way to Remove Stump.

Farm Implement News (Magazine), June 10, 1954, vol. 75, No. 11, pages 114 and 115, r cle Bob Myers is an Iconoclast. 

1. A METHOD FOR SUBSTANTIALLY DESTROYING THE SUBTERRANWAN PORTION OF A TREE STUMP WHICH COMPRISES DISPERSING AT LEAST ONE COMPOUND SELECTED FROM THE GROUP CONSISTING OF THE WATER-SOLUBLE COMPOUNDS OF COPPER AND CHROMIUM WITHIN SAID STUMP IN AN AMOUNT SUFFICIENT TO PROMOTE THE GLOW COMBUSTION THEREOF, AND IGNITING SAID STUMP WHEREBY A SUBSTANTIAL SUBTERRANEAN PORTION OF SAID STUMP IS DESTROYED. 